70 ATC - Gas Cap Vent Clogged?

[Balvar24]

Has anyone ever disassembled the gas cap for the later model 70's? It's the one with the valve built in. I think the one my kids ride is clogged. I'd like to try cleaning it. Runs like a top for 5 minutes and dies. You can almost set a watch by it.

[coolpool]

Loosen it off and try to run it longer, it'll rule out the gas cap issue if it's something else. I've been shown how to drill a 1/16th hole in a 200 style cap to fix that issue but never one as small as a 70.